This invention generally relates to slide-out rooms for use with recreational vehicles and more particularly to a mechanism for controlling the actuation of a slide-out room.
The widths of transportable living quarters, such as recreational vehicles and towable trailers, are limited by highway regulations. Accordingly, many such recreational vehicles include one or more slide-out rooms that can be retracted into the vehicle during travel, and extended from the vehicle to provide additional living space when the unit is parked for use.
Slide-out rooms are typically supported by telescoping supports which are mounted to the frame of the vehicle and actuated by hydraulic rams, electric motors, or similar actuation devices. Typically, two or more such actuation devices are employed, but smaller rooms may use only a single actuation device. Since these actuation devices are often mounted to accommodate wheel wells and other structural components of the vehicle, they may not be symmetrically located with respect to the slide-out room. This may cause unequal loading of the actuation devices, resulting in unsynchronized travel of the room. Additionally, actuation devices may operate at different speeds, even under equal loading. Failure to properly synchronize the motion of the actuation devices may cause undesirable deflection across the length of the room resulting in damage to the room or the vehicle, incomplete seals against weather about the perimeter of the room, and an unsightly appearance of the room. Accordingly, it is desirable to synchronize the operation of the actuation devices to avoid such difficulties. Moreover, it is desirable to calibrate and control the xe2x80x9croom outxe2x80x9d and xe2x80x9croom inxe2x80x9d positions of the actuation devices to assure that the room is fully extended across its entire length when the room is extended for use, and fully retracted across its entire length when the room is retracted for travel.
The present invention provides a hydraulic synchronizer mechanism for a slide-out room that includes a pair of extendable supports that are actuated by a pair of hydraulic actuators or cylinders. Extension or retraction of the hydraulic actuators causes extension or retraction of the extendable supports, thereby moving the room between the extended and retracted positions. Although the invention is described in connection with a pair of hydraulic actuators, the teachings of the invention are equally applicable to actuation systems having three or more hydraulic actuators. Also, while the extendable supports are described herein as mounted to the framework of the vehicle below the vehicle floor, it should be understood that the hydraulic synchronizer of the present invention may readily be adapted by one of ordinary skill in the art to synchronize the movement of extendable members mounted within the vehicle floor or above the vehicle floor.
The present invention further provides a controller which monitors the movement of each hydraulic actuator, and temporarily interrupts the operation of the leading actuator to ensure that both actuators move in unison. The synchronizer may further include sensors or stops to indicate the relative movement of each actuator, and to establish stop limits to set the xe2x80x9croom outxe2x80x9d and xe2x80x9croom inxe2x80x9d positions of the slide-out room.
These and other features of the present invention will become apparent and the invention will be better understood from the following description, with reference to the accompanying drawings.